Kessen III (決戦III) is the final known Kessen title. It implements gameplay elements from the Warriors series and is the longest title of the three. The game claims to recount the history of the Samurai Warriors characters (a similar notation was also made for Saihai no Yukue). In the game's manual, the producer gives the following foreword:

"Kessen III" represents a new style of game play, standing at the confluence of Action and Strategy genres, which unifies the worlds of interactive entertainment and cinema. May you be carried away in the excitement of battle and the thrill of commanding legions of your own troops in your quest for peace and power.

Nobunaga Oda is the uncommonly heroic protagonist with a sincere ambition to end the land's chaos. He and his generals visually age as the game progresses and adopt a new attire various times throughout the game. As time passes, Tokichiro and Motoyasu will also be called by their recognizable historical names. The game's story remains modestly faithful to his historical battles until Mitsuhide's betrayal at Honnoji. Additional playthroughs unlocks cinematics that show a second side to the story as well as an additional ending.

It is the only game in the series to include a dual language option, allowing the player to switch between the English and Japanese voices. Kessen III and Fist of the North Star: Ken's Rage 2 are the highest ranked Koei titles in the Famitsu charts with a score of 37 out of 40 (10/9/9/9).

Contents

The time spent between battles in which Nobunaga and his closest allies plan their next step from their home base. Each chapter has three types of battles: minor, major, and decisive. Minor battles are on the side and are the best ways to earn extra experience. Major battles affect the story's progress and are sometimes available for a limited amount of time. Decisive battles are often the concluding confrontation in the chapter and opens more fights on the map.

Players can also use this time to buy equipment for their army such as troop types, horses, weapons, manuals, accessories, and armor. Equipping items additionally changes the character's appearance so the player is free to customize their army's appearance. Aesthetics only affect the visuals in the planning and battle stages; they will not change in the game's pre-rendered cinematics.

Unlike the previous titles, the stats and capability of an officer are explored in depth. Their progress is now visually charted through a leveling system similar to the Warriors games with the maximum level being 50. Experience is gained by participating in battle, defeating an enemy officer, or scoring more items in the Rampage sequence. Rank determines the number of soldiers they lead into battle.

The brawlers; learns skills slowly but starts with two Kessen Attacks during Rampages

Tactician

WarIntelligence

TacticalOffensive

Warriors who focus on whittling the enemies offense; well balanced support unit

Priest

IntelligenceStamina

SupportTactical

Frail yet useful support units; best magic casters

Ninja

WarIntelligenceStamina

Ninjutsu

Best type of officer to lead ninja troops; strong yet comparatively few in number

Similar to the first title, officers may experience different levels of fatigue. Their condition is shown by a colored arrow next to their names, a green upright arrow being the highest (Excellent) and a downwards red arrow being the lowest (Down). Generally, a vassal who continuously participates in battle will have a faltering condition while resting units will be in better shape.

Winning against an officer in a Rampage raises their state one level; losing will lower their condition by one. If an officer is routed in battle, they will return in a Down state. Officers in their optimum condition have better fighting power and all four Skill Slots filled.

The time when players decide how to place their units on the battlefront. The presentation of this phase depends on the type of battle that the player chooses. In minor battles, the only information given is presented on the map. During decisive and major battles, Nobunaga will be presented with reconnaissance data regarding the enemy's location, ally reinforcements, and other participants on the field. Before deciding his units' positions, one or two generals will personally address their lord. These speakers will often be in Good or Excellent conditions for this battle.

After the initial sequences, the player is given the chance to place their men on the field. Similar to the first title, their vassals' possible locations are marked by a white box with a x in the middle. Each army is usually lead by one main general and two minor generals that serve them. During confrontations that affect the game's story, dull gray units on the map are mandatory and cannot have their position changed. The player can make last minute changes to their officers' equipment before sending them out on the field.

Hints and the conditions for victory can be checked in the data box on the left side of the screen. Additionally, players can choose to let the computer auto deploy their units on the field.

Battles all have a ranking system that judges how well the player has performed based on their time, troops killed and lost, and successful troop skills. Earning a S rank is often the only way to unlock rare items and unit types. Additionally, some ally generals will only appear to Nobunaga if their previous battle rank was high. If the rank the players receives is unsatisfactory, they are always given a chance to retry the battle.

Taking inspiration from Kessen II, armies can be ordered to move from an overhead map and manually controlled by the player on the field. While minor generals cannot be ordered to move, the player can select them and move them to perform a separate task. Players can choose to rearrange their armies in battle to reassign a new leading general or to create individual armies from minor generals that the player can control.

The importance of keeping an army in formation is emphasized with the newer level of movement. When an army loses its shape, it moves slower and is prone to losing unexpected numbers. Holding R1 calls for traveling men and retains the army's ranks.

When two opposing armies first face each other on the field, they have the chance to ram each other for damage. The basic battle controls are similar to the Warriors series: and serves as the army's basic attacks and guarding/strafing is performed by pressing L1. Attacks can be combined in a Warriors manner with different effects (i.e.: ,,, will make the first line of men charge into enemy ranks).

Retreating is no longer an order-only command as players can withdraw their unit from battle by moving and holding . The fleeing unit will have lower defense and cannot perform any other actions.

Various items and people on the field are symbolized on the map as glowing golden objects. Items can either restore lost troops or contain new equipment or unit types. People can reveal new hints about the enemy or be recruited after the battle.

Defections and ambushes are triggered by the player's movement on the field. When an enemy army is confused, they cannot take any action and will have a lower defense.

Allows players to begin playing. A higher level of difficulty is unlocked once the player clears the game on a different setting. To fully experience the game's story, three or four cycles are required.

The gallery section that displays all acquired movies, equipment, generals, and battles. Battles display a brief description, some historical info, and allow the player to replay for better rankings. If the player unlocks the game's secret battles, they can also gain new items or unit types for their second play through.

A pachinko machine known as CR Kessen ~ Amakakeru Hasha was made by Nishijin with this game's visuals. It was put in pachinko parlors in November 2009. It features new themes separate from the original soundtrack, new renders of the character models, new cutscenes, and borrows animations used in Kessen and the Samurai Warriors series. Its image song is Shijou no Yorokobi ~Itoshiki Hito no Tameni (至上の歓び～愛しきひとのために～) and is performed by Myuji.

Super-deformed figurines of Da Qiao and Yukimura Sanada appear as two objects from Tokichiro's goods. Nobunaga says he'll take everything the merchant has and two soldiers run off holding said figurines.

When Toshiie first starts out, he is seen wielding Yukimura's third weapon from Samurai Warriors. Guan Yu's weapon, known as "Blue Dragon Yinyuedao", can also be unlocked late in the game. Lu Bu's characteristic weapon of choice from Romance of the Three Kingdoms also makes an appearance.